Why has my Photoshop CS2 stopped working? [Windows 10]

[David24459372brve]

I've been using Photoshop CS2 for, like, forever, and yet today, when I started the programme, it tells me that the license has expired and I need to enter a new key ... but I've been using the version with key from the Adobe website for about 10 years ... and I thought it was fine ...  Now there seems no way to activate as the activation servers are not available ... and the key is not recognised.
I don't want to upgrade to the current version as I know how CS2 works and have no wish to change to something which will be totally different ... so what has happened here?
Hopefully it's a glitch and will be OK later on ... except that the key I had seems to now not be detected as 'correct' ...

Thanks so much! I'm on Windows 10 ...

["Windows 10" added to subject by moderator]

[Peru Bob]

You may have software that cleans cookies and/or the registry that "disconnected" your CS2.

The CS2 activation servers have been shut down, so there is no way reactivate CS2.

Perhaps System Restore might fix it for you.

If not, you may want to have a look at Photoshop Elements which is a one time purchase.

[David24459372brve]

Thanks for the response, but that's not it 😞  No idea what's causing it unfortunately ...